PMEngineer September 2016 : Page 24

Tech Topic: Copper Piping By Andrew G. Kireta Jr. | andrew.kiretajr@copperalliance.us A lurking problem Copper pipes can be a reliable replacement for lead service lines. ou’ll stare at it, but you won’t see it. You’ll consume it, but you won’t taste it. It is an invisible problem lurking within pipes and affecting cities across the nation. This may sound like a trailer for a thriller movie, but in reality it’s the serious water crisis currently confronting America. A recent study by the American Water Works Association (“National Survey of Lead Ser-vice Line Occurrence”) estimates there are about 6.1 million lead service lines in the ground across 11,200 community water systems in the United States. However, the lack of real lead service line inventories by many public water systems could mean this estimate is conservative. As local officials, building owners and taxpay-ers grapple with how to deal with the risk posed to drinking water, they are making decisions on piping replacement that can have effects long into the future. Y Lead and drinking water don’t mix Lead itself is not inherently bad. It is a vital component of the lead-acid battery – a technology that powers our lives every day. In fact, lead once was prized for its longev-ity and formability — at one time making it the preferred piping material. By 1900, more than 70% of cities in the U.S. with popula-tions greater than 30,000 were using lead water lines. However, warning signs began popping up as the health impacts of the ingestion of lead started to become known. When ingested, lead is a serious neu-rotoxin with severe adverse health effects associated with even very low intake con-centrations. In fact, according to the Envi-ronmental Protection Agency, no amount of lead ingestion as indicated by blood lead levels is safe for children. Lead intake can cause developmental delays, irreversible cognitive and behavioral problems, anemia, seizures, coma and other adverse health issues. To address the problem and reduce the risk of lead exposure through drinking water, the EPA instituted stringent require-ments on the amount of lead that can be present in drinking water before actions must be taken. While there are many com-pounds controlled by the Safe Drinking Water Act, the levels at which they are con-trolled show their relative potential impact on health. Lead is regulated at 15 parts per billion in water, 87 times more restrictive than the 1,300 ppb allowable for copper. In some ways, this is all old news. Cop-per and other materials have long since replaced lead in new construction – so this problem is one of remediating the past since many cities have yet to replace old lead service lines. However, Flint, Mich., among many other municipalities, has brought to the forefront the inherent risk in not addressing the large volume of lead service lines buried within the aging water infra-structure of the country — a risk that with one change of the water supply or water treatment can expose citizens to unsafe lev-els of lead in their drinking water. In Flint, corrosive waters from the Flint River com-bined with a lack of corrosion control treat-ment caused aging lead pipes to leach into the water supply, resulting in toxic levels of lead in drinking water. Between six and 12,000 children may have been exposed. Now, homeowners and city officials from around the U.S. have suddenly become hyper-aware of the quality of their drinking water and the importance of their water infrastruc-ture. A 2016 review of the EPA enforcement data by USA Today reveals nearly 2,000 drinking water systems serving six million people in all 50 states have experienced excessive or harmful levels of lead, with 373 of these systems repeatedly failing for exces-sive lead. Perhaps the best way to eliminate the risk now and for all future generations is to remove and replace all lead service lines from our critical water infrastructure. We are entering what many are referring to as the “Replacement Era,” a time where much of our nation’s drinking water infra-structure needs to be replaced. The deci-sions city officials and homeowners make and the materials they select will have con-sequences long into the future. They could choose the “short-term money-saving option” that has the potential to leach small amounts of contaminants that do not offer any health benefits or for which their health impacts are not fully known and are being considered, or they could choose to make an investment by selecting what 80% of all utilities choose for service lines — copper. 24 09.16 Photos credit: John Catterall